The invention relates to a cooling water pump for an internal combustion engine with a housing provided with a bearing designed to support a pump shaft and with a sealing element devised to seal the bearing against a working area containing the cooling agent as well as with a leakage chamber receiving the cooling agent that oozes through the sealing element, wherein the leakage chamber is arranged in a recess of the housing and is provided with an opening to the outside, said opening being partially closed by a locking device.
Cooling water pumps in motor vehicles are exposed to relatively critical working conditions. Long rest periods and great variations in temperature are to be overcome and maintenance-free operation over a long period of time is taken for granted. In practice it proved to be almost impossible to achieve a perfectly tight sealing of the pump, i.e., the oozing of small amounts of cooling agent must always be taken into account. It is however absolutely unwanted to let this quantity of leakage run out of the pump without further ado, since this would produce the impression of a defect.